All through service trains enter the Tōzai Line at either Nakano, or Nishi-Funabashi.

These trains operate within the following routes: Prior to March 2024, seasonal Limited Express Shinjuku Wakashio and Shinjuku Sazanami trains stopped at Akihabara on the Chūō-Sōbu Line "mainly on weekends and holidays when service is heavy".

[2] At around 9 -10pm, a few westbound trains headed beyond Mitaka onto the Chūō Line (Rapid), with some terminating at Musashi-Koganei, and the others at Tachikawa.

At around 4 - 6am and 11pm - 1am, Chūō-Sōbu Line services were divided at Ochanomizu Station, into two sections.

Women-only cars, designed to prevent gropers, were introduced on this line during morning peak periods starting on 20 November 2006.